A conventional buckle generally includes a male fastener and a female fastener. Another conventional buckle further includes a combination lock for controlling connections between the male fastener and the female fastener. As disclosed in Taiwan Patent No. 188582, a buckle, namely an elastic-type buckle, is provided for fastening luggage with a strap; furthermore, a combination lock is provided for controlling whether the strap can be released.
Additionally, US publication No. 2005/0155397 discloses a buckle with a strap that includes not only a combination lock but also a key lock cooperated with the combination lock so that the strap can be released via two different ways. One way is to dial a set of correct codes of the combination lock so as to allow a male fastener of the buckle releasing from the female fastener of the buckle. Another way is using a key to unlock the key lock so as to allow the male fastener of the buckle releasing from the female fastener of the buckle. Accordingly, such a buckle provides a benefit that a user can unlock the buckle via the combination lock, and a luggage inspector can unlock the buckle via the key lock by using a master key, which is unique and held by the inspector only. Therefore, the luggage can be open and inspected without damaging the buckle.